1. Field of the Invention
This invention relates to telephone answering devices (TADs) and particularly to TADs that answer a telephone line accessible by more than one telephone number.
2. Description of the Related Art
Telephone answering devices are now commonplace in today's society. With most TADs, incoming telephone calls are answered, are delivered a pre-recorded outgoing message, and the caller is given opportunity to record his or her message for later playback by the TAD's user. When the TAD is connected to a telephone line which is accessed by only a single telephone number, there is often no reason to have more than one outgoing message delivered to callers. In such a situation, the outgoing message may be delivered in whatever context the user chooses.
Recent advances in the art allow the individual user more flexibility in telephone service. New advances in telephone service include: automatic dialing through the telephone exchange (speed calling), allowing a second incoming caller to notify the called party that a second call is coming in (call waiting), and the ability to transfer an incoming call to another number when the user is away (call transfer).
One further development is the ability for two telephone numbers to share the same incoming telephone line. One reason for this feature is the increasing use of the home as a professional workplace. The user may have two telephone numbers, one for personal calls and the other for business, that both ring the same physical telephone in the user's home. As a person may want to know when the incoming call is to the business number and when the call is to the personal line, one useful way to distinguish the incoming calls is by having the telephone ring differently depending upon which number is being called. This feature has been termed "distinctive ring".
As an example, one way for the telephone to ring differently is to have different cadences of telephone ring sequences depending upon which number is being called by the caller. The personal line could ring normally while the business line could ring twice as fast, twice as slow, or with another different and readily identifiable ring sequence. The use of distinctive ring sequences that depend on the number being called prepares the called person for the type of call being placed.
Distinctive ring patterns are typically generated by intermittently ringing the telephone for a certain period of time, then maintaining a gap of silence for another certain period of time. For one example of a distinctive ring pattern, the telephone may give off three short ring signals, remain silent for a second or two, then repeat the pattern until the telephone is answered or the caller hangs up.
As people do not stand sentry over their telephones waiting for them to ring, the telephone may be left unattended for long periods of time. TADs have previously provided means by which telephone messages could be received when the incoming call would otherwise go unanswered. Previously, two separate TADs were required for two separate telephone lines, one TAD for each number. The earlier related art did not address the problem of answering the telephone and recording messages from it when two telephone numbers accessed the same telephone. Earlier art treated both types of calls the same by playing the same outgoing telephone message to the caller whether or not the caller called the business telephone number or the personal telephone number.
The mechanism for identifying the distinctive rings and routing the incoming calls to systems is known in the art. For example, a device called the Fone Filter, manufactured by South Tech Instruments of Hollywood, Fla. assigns a different ring pattern to each connected device and automatically routes the calls to the appropriate device, based on the corresponding ring pattern that is received.
Another unsolved problem with answering machines is that whenever a user picks up the handset during the answer ring cycle, that is the ring cycle upon which the telephone answering device (TAD) automatically answers the telephone line, the TAD automatically plays the outgoing message even though the answering machine was set up to answer only if no one answered the telephone. This occurs because as soon as the handset is picked up, the ring cycle is interrupted and the answering machine wrongly assumes that the ring cycle has ended naturally without anyone picking up and answering the telephone. In other words, picking up the handset automatically triggers the Out Going Message (OGM) though clearly that is not what is desired or best. No known solution exists in the art, although a partial solution is present.
In order to partially solve this problem, the OGM can be set up to stop playing if the handset is picked up during the OGM or message recording. This mechanism is commonly referred to as Auto Disconnect which senses the drop in line voltage caused by the handset going off hook.
Although well known in the art, the Auto Disconnect mechanism does not suppress the OGM when the user picks up a parallel telephone or extension during the answer ring cycle. When the user picks up during the answer ring cycle, the voltage drop occurs before the answering machine is on the line and the Auto Disconnect circuit is unable to detect the telephone going off hook. The TAD continues to proceed by playing the OGM and recording a message.
An information disclosure statement has been submitted regarding this patent. The following list contains previous patents potentially related to the present invention:
U.S. Pat. No. 3,193,620 issued to Marheine on Jul. 6, 1965; PA0 U.S. Pat. No. 3,679,831 issued to Bonsky on Jul. 25, 1972; PA0 U.S. Pat. No. 4,626,631 issued to Hanscom on Dec. 2, 1986; PA0 U.S. Pat. No. 4,646,347 issued to Liu on Feb. 24, 1987; PA0 U.S. Pat. No. 4,782,518 issued to Mattley et al. on Nov. 1, 1988; PA0 U.S. Pat. No. 4,926,470 issued to Sanford on May 15, 1990; and PA0 U.S. Pat. No. 4,985,913 issued to Shalom et al. on Jan. 15, 1991. PA0 U.S. Pat. No. 3,555,189 issued to Quatse on Jan. 12, 1971; PA0 U.S. Pat. No. 4,066,848 issued to Darwood on Jan. 3, 1978; PA0 U.S. Pat. No. 4,117,272 issued to Ando on Sep. 26, 1978; PA0 U.S. Pat. No. 4,356,355 issued to Ferrieu et al. on Oct. 26, 1982; PA0 U.S. Pat. No. 4,390,843 issued to Betts et al. on Jun. 28, 1983; PA0 U.S. Pat. No. 4,484,036 issued to Lyle et al. on Nov. 20, 1984; PA0 U.S. Pat. No. 4,731,828 issued to Basehore on Mar. 15, 1988; PA0 U.S. Pat. No. 4,939,775 issued to Houck et al. on Jul. 3, 1990; PA0 U.S. Pat. No. 4,975,940 issued to Hashimoto on Dec. 4, 1990; PA0 Japanese Patent No. 57-131159 issued to Sakamoto on Aug. 13, 1982; PA0 Japanese Patent No. 2-65351 invented by Takenaka and issued to Sharp Corp. on Mar. 6, 1990; PA0 Soviet Patent/Certificate of Invention No. 760479, application no. 2312145/18-09, filed on Jan. 12, 1976.
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